Railway car brake inspection utilizing a radioactive source and detector



June 1, 1965 w, KELLER 3,187,181

RAILWAY CAR BRAKE INSPECTION UTILIZING A RADIOACTIVE SOURCE AND DETECTORFiled Feb. 5, 1965 2 Sheets-Sheet l 6 I'll/all! g? .5/ c I A COUNTER m jv K I l I I '37 J0 55 Z5 26 INVENTOR.

mm/wkllen United States Patent O 3,187,181 WAY CAR BRAKE DJSPETEQNUTEIZENG A RADIGACTIVE SQURCE AND DETECTGR William M. Keller, 8354 E.Prairie Road, Skoisie, Ill. Filed Feb. 5, 1963, Ser. No. 256,494 11Claims. (Cl. 250-83) This invention relates to means for automaticallyindicating conditions of brake application and release on each of therailway cars in a train being checked for proper brake operation.

The proper brake operation on all the railway cars in a train isextremely important because there is always a danger of grave injury ordeath to persons and extensive damage to equipment and lading if thebrakes on all railway cars do not operate properly during train service.Consequently it is required by law that an examination of the brakesystem on each railway car must be made before a train departs or leavesthe car yard after the train has been made up. An important part of thisexamination consists in checking whether or not there is proper brakeapplication on each car during the time that the brakes are supposed tobe applied and whether .or not the brakes on all cars are released whenthe signal is given for this portion of the examination.

In the past it has been necessary for an inspector or team of inspectorsto walk the entire length of a train to physically check the conditionof the brake system on each car during brake application and to repeatthis check during brake release operation. This, of course, is a timeconsuming and expensive process and it is a primary object of myinvention to provide means for automatically inspecting railway carbrakes so as to eliminate the time delay and expense involved in thepresent method of an inspector or inspectors walking the length of thetrain.

A further object of my invention is to provide means which are designedto automatically inspect the brake systems on individual railway cans ina train and transmit the results of this inspection to a track waysidestation.

A still further object of my invention is to provide a source ofradiation which is mounted on each railway car and which cooperates witha relatively movable track mounted radiation detector to actuate signalmeans at a track Way-side station so as to automatically monitor theoperations of brakeapplication and brake release on each railway car ina train.

Other objects and advantages of my means for automatically inspectingrailway car brakes will be apparent during the course of the followingdescription.

In the accompanying drawings forming a part of this specification and inwhich like numbers are employed to designate like parts:

FIGURE 1 shows an end view of a railway car which is partially cut awayto reveal the arrangement of the radiation emitter control unit that ismounted on therailway car, the associated radiation detector unit, andthe instruments located in the track wayside scanning station.

FIGURE 2 shows the structural features of the radiation emitter controlunit which is connected with the brake system of the railway car in themanner shown in FIGURE 21.

FIGURE 3 is a plan View of the radiation detector unit on the movablecarriage.

Most railway cars now in operation on the railway lines of the UnitedStates are provided withan air brake systemwhich is designed to beinterconnected with the air brake systems of other railway cars in'atrain. Thus, I

on each railway car there is a brake pipe that extends throughoutthe'length of the railway car with an angle cock and hose at each end ofthe car which are' designed to be connected to the correspondingequipment on the adjacent cars. Through these pipes and fittings: com

pressed air from a source on the train engine can be' supplied to adouble compartment reservoir on each car. When the air brake system oneach railway car is thus charged to a predetermined minimum, this energyis avail able for use when it is desired to apply the brakes. In orderto apply the brakes on the cars in a train, the engineer reducespressure in the brake pipe which in turn actuates valves in theso-called AB valve. This AB valve then permits an air fiow from thereservoir on the car to a brake cylinder with a movable piston thatoperates to actuate a linkage system and apply the brake shoes to thewheels of the car. Brake release is effected by releasing the compressedair from the brake cylinder. The system thus far described is common topower brake installations on most railway cars today.

The elements of my invention, which are adapted for use with the abovedescribed railway car air brake system, consist generally of acar-mounted radiation emitter control unit which carries a source ofradiation capable of emitting gammarays or other forms of radiation, amovable track-mounted radiation detector unit designed to be responsiveto the source of radiation under certain conditions of brakeapplication, and a track wayside scanning station adapted to receivesignals from the radiation detector unit and to process such signals forevaluation.

The radiation emitter control unit on each railway car is associatedwith the air brake cylinder of the air brake system so that whencompressed air is admitted to the air brake cylinder to apply thebrakes, this compressed air will also move the source of radiation to aposition wherein the radiation emitted from the source can be detectedby the radiation detector unit. When the brakes of the railway car arereleased by the reduction of air pressure in the air brake cylinder, thesource of radiation is maintained by suitable means in a shieldedposition with respect to the radiation detector unit.

In the embodiment illustrated by the drawings, the radiation detectorincludes a sodium iodide crystal, a photo tube, and an amplifier. Thesodium iodide crystal acts to convert gamma ray radiation into lightrays which are in turn converted by the photo tube into electricalcurrents that can be suitably amplified by the amplifier. The radiationdetector unit is designed to be moved by suitable means along insulatedrails mounted on the track ties be tween the rails of the main track onwhich the train moves so that the sodium iodide crystal can scan theradiation emitter control units on each of the railway cars during itspassage along the length of the train being inspected.

Means are provided for transmitting the outupnt signals from theamplifier of the radiation detector unit through the insulated rails toelectronic instruments'at a track Wayside scanning station for recordingand counting the signals received from the individual radiation emittercontrol units.

While I heretofore have referred to'the fact that my system forinspecting railway car brakes is adapted for use on railway cars with anair brake system having certain components, it should be obvious that myautomatic inspection system can be readily used with any type of railwaycar brake system in which a fluid, either gaseous or liquid, is admittedunder pressure to a cylinder or housing to effect an application of thebrakes, and in which a predetermined reduction of the fluid pressure inthe cylinder or housing is efiective to release the brakes.

In FIGURE 1 of the drawings. the railway car is genorally designated atiii and includes the usual center sill ll, truck bolster 1'2, and a caraxle 13 carrying a flanged wheel 14 adjacent each of its ends to supportthe car on rails 15. The specific structure-of the railway car is notimportant With'regard to my invention, and theabove described featuresof the railway car are well known;

The railway car'lil is equipped with a brake system, a

, emitter control unit 23.

"valve 16 is operated to admit compressed air to the air 3;. portionofwhich. is shown in FIGURE 1. This portion includes the AB brake valve 16or other suitable valve through which compressed air is admitted to orreleased from the air brake sylinder designated at 17. A portion of theair brake cylinder piston rod is shown at 18. The

other elements of the railway brake system for the car 'are not shownbut as previously mentioned and briefly described, suchsystem is'wellknown in the art. The AB automatically inspecting railway car brakes,contains a movable source of radioactive radiation, and while thedescription hereinafter refers to the emission of gamma rays from thissource of radiation, my invention contemplates the use of other forms ofradiation with a track- .mounted radiation detector unit which isdesigned to detect these particular forms of radiation. As an example,it is within the scope of my invention to provide a movable source oflight rays within the radiation emitter control unit 23 which could beassociated with a trackmounted radiation detector unit having a phototube.

The details of the radiation emitter control unit 23 are shown in FIGURE2 and it can be seen that air line 22 is secured to the radiationemitter control unit at one end thereof by means of an internallythreaded cap 24. The radiation emitter control unit includes acylindrical housing portion 25 which is threaded to a second housingportion 26. A piston 27having a piston rod 28 isslidably received withinthe housing portions 25 and 26. The

piston 27. is urged by coil'spring 29 to a position as illustrated inFIGURE 2 so as to close an opening 30 that is aligned with an open endof air line 22. The other end of the coil spring29 rests against acollar 31 which in turn is supported by a shield insert 32 receivedWithin the second housing portion 26 of the radiation emitter controlunit 23. The shield insert 32 is of lead or suitable radioactiveradiation insulating material to provide a shield for the source ofradiation which is indicated at 33 and which is carried at the end ofpiston rod 28. It will be noted that near one end of second housingportion 26 there is a window 34 extending completely through the secondhousing portion. 26 and the' shield'insert 32 to provide an opening fromthe cavity 35 in which the source of radiation 33 is movable.

In considering the use of the above described radiation emitter controlunit in conjunction with the brake system of the railway car, it shouldbe apparent that the AB brake valve 16 controls the introduction andrelease of compressed air not only to the air brake cylinder 17, butalso to opening 30 in the radiation emitter control unit.

When there is no introduction of compressed air to the -air brakecylinder 17, the brakes of the car air brake system will normally be inbrake release position and at this time coil spring 29 of the radiationemitter control unit will be effective to maintain the piston 27 at theposition shown in FIGURE 2. In this position the source of radiation33'is in a location remotefrom the window 34 so that the shield insert32 is effective to stop any appreciablegamma ray radiation outside ofthe radiation brake cylinder 17, compressed air will also be deliveredHowever, when the AB brake The detector unit for detecting gamma raysemitted from the radiation emitter control unit 23 is generallydesignated at 36. The detector unit 36 is mounted on a movable carriagegenerally indicated at 37. The movable carriage 37 has steel wheels 38which are mounted on axles 39 so as to ride on rails 40, and these rails40 are in turn mounted on insulation pieces 41 carried along the ties 42of the railroad track. Axles 39 have insulated joints at 43 so that thetwo steel wheels 38 on each of the axles 39 are electrically isolated orinsulated from each other. Each portion of the axle 39 on opposite sidesof each'of the insulated joints 43 carries a slip ring 44, which slipring can be of well known construction to provide for an electricalcontact to the axle 39.

The carriage 37 can be moved along rails 40 by a suitable means such asanelectric motor drive to the steel 7 wheels 38 of the movable carriage37 or by any other through air line 22 and opening 34 to act againstpiston 27 and the piston rod 28 will be forced away from opening 30against the restraining influence of the coil spring 29. As'the sourceofradiation 33 is carried at the end of piston rod 28, this movement ofpiston rod 23 will move the source of radiation-33m a position inalignment with the window 34 and gamma rays will be emitted through thiswindow 34.

' 52 and recorder 53.

means such asa cable drive or other mechanical means. In FIGURE 3 I haveshown the use of electric motor 45 to rotate axle 39 through a chaindrive, generally indicated at 46. Electric current-for electric motor 45can be furnished through rails 40, steel wheels 38 and axle 39 to eachof the slip rings 44 mounted on the axle. Electric wires 47 and 48 areconnected between these slip rings and the electric motor 45 to deliverelectric power to the electric motor.

As shown in FIGURE 1, the rails 40 are also connected through wires 49and 50 to electronic instruments at a track wayside station. Wire 49 isconnected to wire 51, and wire 51 provides a common connection to adigital counter generally indicated at 52 and to a recorder generallyindicated at 53. Wire 50 is connected to wire 54 providing. a commonconnection betweendigital counter 52 and recorder 53. The digitalcounter 52 and recorder '53 are generally indicated and as units of thisgeneral not the brakes were applied. Onemethod of accomplishing theseresults would be to use a stepping relay (not shown) on the digitalcounter 52 and have this relay actuate a double-acting relay (not shown)which would show a mark on the recorder 53 for each car in the train toindicate whether or not the brakes on that car are applied.

The detector unit 36 includes a sodium iodide crystal 55, an associatedphoto tube 56 and a suitable amplifier 57. As previously mentioned, thesodium iodide crystal 55 has the ability to convert gamma rays to lightrays and these light rays are of, sufiicient intensity to activate thephoto tube 56 disposed adjacent the sodium iodide crystal 55. 1Electrical impulses from the photo tube 56 are trans rnitted throughwires 58 and 59 to amplifier 57. Amplifiers for amplifying the electriccurrent output of a photo tube such as 56 are well known in the art andtherefore no specific description ofthecircuitry of such an amplifier isdeemed necessary. The electric current output of the amplifier 57 is fedthrough wires 60 and 61 to slip rings 44 on the axle 39 whichis notdriven by electric motor "electric currents or signals from amplifier 57to the digital counter 52 and recorder 53 at the wayside scanningstation.

It should be noted that rails 40 provide electrical circuit means for.the supply ofelectriccurrentto the electric motor 45 and also for theelectrical output of the radiation detector unit'which is being fed tothe digital counter The operation of; my automatic brakeinspectiondevice should now beapparent from theabove description. The

line of individual railway cars comprising the train will be spotted onthe section of track having the insulated rails 40 for carrying movablecarriage 37. This movable carriage 37 can be moved along rails 40 bysuitable means such as electric motor 45 to carry the detector unit 36along rails 40 for the entire length of the train to monitor thecondition of brake application. After the signal for the brake releaseoperation, movable carriage 37 can be moved back along the entire lengthof the train to monitor the condition of brake release. If desired, thetrain can be moved during the time of brake release and the movablecarriage 37 can be maintained at one position to scan the passingradiation emitter control units on the individual railway cars.

The sodium iodide crystal 55 of detector unit 36 must, of course, bepositioned so that as there is a relative movement between the carriage37 and each of the cars in the train, sodium iodide crystal 55 will passdirectly adjacent the radiation emitter control unit 23 and the sodiumiodide crystal 55 will "be generally aligned with the window 34 in theradiation emitter control unit 23. Thus in the first passage of themovable carriage 37 along the entire length of the train, the sodiumiodide crystal 55 succussively passes the windows 34 of each of theradiation emitter control units 23 mounted on each car of the train.During this passage the air brake system has been activated so that theAB brake valve 16 on each car has supposedly operated to supplycompressed air to the air brake cylinder 17 on each car and also supplycompressed air to move the piston 27 and piston rod 28 of radiationemitter control unit 23 on each car to a position where the source ofradiation 33 is aligned with window 34. Thus, assuming that the brakeson all cars of the train have been properly applied through the supplyof compressed air to each of the air brake cylinders 17, then the sodiumiodide crystal 55 will receive gamma ray radiation from each of theradiation emitter control units 23 on each of the railway cars in thetrain. This gamma ray radiation will be converted to electrical currentsor signals which are transmitted to the track wayside scanning sta tionhaving the digital counter 52 and recorder 53 for processing. If forsome reason there has not been an application :of compressed air to theair brake cylinder 17 on a particular car so as to apply the brakes,then the source of radiation 33 will remain in the shielded position asindicated in FIGURE 2 and the sodium iodide crystal 55 will receive nogamma ray transmission from that particular radiation emitter controlunit 23 on that car. This fact will, of course, be noted by the digitalcounter 52 and the recorder 53 at the track wayside scanning station sothat corrective action can be initiated.

On the return trip of the movable carriage 37 or when the train of carsis moved over this carriage, the sodium.

iodide crystal 55 will be scanning each of the radiation emitter controlunits 23 on the individual cars of the train to ascertain whether thesource of radiation 33 is in' The foregoing description of my inventionis made for the purpose of disclosure and to illustrate the principlesinvolved, and will suggest various substitutions and changes that may bemade under my basic concept. The right is reserved to all suchsubstitutions and modifications that lie within the scope of theappended claims.

I-claim: i

1. An automatic inspection system for railway car brakes, comprisingfirst means a ss-ociated'with a brake cylinder and piston, said firstmeans including a source of radiation, second means relatively movablewith respect to said first means and adapted to convert radiationreceived from said Ifirst means into electrical currents, said source ofradiation being urged to a shielded position with respect to said secondmeans in the absence of a fluid pressure application against .the brakecylinder piston, said source being moved from said shielded position toanother position wherein radiation from said source impinges upon saidsecond means when there is a fluid pressure application against thebrake cylinder piston, and means associated with said second means toprocess and record said electrical currents.

Q. An inspection system =for use with a railway car brake systemincluding a source of gamma rays associated with a brake cylinder andpiston, means for converting gamma rays into electrical currents andbeing movable relative to said source, second means for receiving saidelectrical currents and processing said currents to indicate brakeapplication or release on the railway car, said source being shieldedfrom said means during normal brake release conditions and being moved.to a position to emit radiation to said means during normal conditionsof brake application.

6. An inspection system tor indicating brake application and release ona railway car, including a source of gamma rays associated with the carair brake system and movable to a tfil'St position during proper brakeapplication and movable to a second position during pro-per brakerelease condition,-a detector (for converting gamma ray emission toelectrical currents, said gamma rays affecting said detector in saidfirst position, and means associated with said detector to process andrecord said electrical currents.

'4. An inspecting system for indicating brake application and release ona railway car, including [first means associated with the brake cylinderof the railway car brake system, a second means movable relative to saidfirst means, said first means including a source of gamma rays which isshielded from said second means during the period of normal brakerelease and which impinges gamma ray radiation on said second meansduring the period of normal brake application, said second means beingcapable of converting the gamma rays received from said first means intoelectrical currents.

S. The system as specified in claim 4 wherein said first means includesa housing with a slidable piston and piston rod therein, said piston rodcarrying said source V of gamma rays at one end thereof, resilient meansurging said piston to a first position wheresaid source of gamma rays isshielded inom said second means during periods of normal brake release,and an air line connected from the brake cylinder to the housing so thatthe application of compressed fluid to said bnake cylinder, whichnormally efiects bnakeapplication, is also effective to force saidpiston and'source of gamma rays to a second position where the gammarays impinge on said second means.

6. The system as specified in claim 5 wherein said second means includesa sodium iodide crystal and vassociated photo tube which is operativelyconnected through an amplifier to a wayside scanning station havingsignal processing means therein.

7. The system as specified in claim 'dwherein said signal processingmeans includes a digital counter and a recorder.

8. Apparatus for inspection of brake application and brake release oneach of a plurality of railway cars connected in a train with an airbnake system, including a source of radiation on each car to emit gammarays, said source being associated withthe air brake cylinder -on thecar, second means mounted adjacent the train for progressive movementpast each car of the train, said second means carrying a detector unitadapted to mitting position with regard to said second. means during theperiods of normal brake application and being urged to a shieldedposition with regard to said second means during periods of normal brakerelease.

*9. The apparatus as defined in claim 7 wherein said second means ismounted for movement on rails dis posed beneath the cars of the trainand wherein the source of radiation is mounted on the underside of each7 'said source being urged to an inoperative position with respect tosaid detector means during periods of normal brake release and beingmovable to an openative position by a fluid pressure application in thecar air brake system designed to effect a normal brake application.

11. :The' system as defined in claim 10 wherein said 5 detector means isadapted to be relatively moved with respect to the: railway cars of thetrain.

References Cited by the Examiner UNITED STATES PATENTS 10 3,076,0891/63' Spalding 250-106 X 3,090,859 5/63 Rodin 250-106 X FOREIGN PATENTS817,567 7/59 .Great Britain.

15 RALPH G. 'N'ILSON, Primary Examiner.

ARCHIE R. BORCHELT, Examiner.

1. AN AUTOMATIC INSPECTION SYSTEM FOR RAILWAY CAR BRAKES, COMPRISINGFIRST MEANS ASSOCIATED WITH A BRAKE CYLINDER AND PISTON, SAID FIRSTMEANS INCLUDING A SOURCE OF RADIATION, SECOND MEANS RELATIVELY MOVABLEWITH RESPECT TO SAID FIRST MEANS AND ADAPTED TO CONVERT RADIATIONRECEIVED FROM SAID FIRST MEANS INTO ELECTRICAL CURRENTS, SAID SOURCE OFRADIATION BEING URGED TO A SHIELDED POSITION WITH RESPECT TO SAID SECONDMEANS IN THE ABSENCE OF A FLUID PRESSURE APPLICATION AGAINST THE BRAKECYLINDER PISTON, SAID SOURCE BEING MOVED FROM SAID SHIELDED POSITION TOANOTHER POSITION WHEREIN RADIATION FROM SAID SOURCE IMPINGES UPON SAIDSECOND MEANS WHEN THERE IS A FLUID PRESSURE APPLICATION AGAINST THEBRAKE CYLINDER PISTON, AND MEANS ASSOCIATED WITH SAID SECOND MEANS TOPROCESS AND RECORD SAID ELECTRICAL CURRENTS.